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Building an adjustable constant current load

Posted on Monday, January 21st, 2013 in project logs by DP

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Here’s a project log covering the build of an adjustable constant current load. It’s capable of sinking up to 7A, and can withstand input voltages up to 60V. The log covers the design, perfboard assembly, and case assembly.

An adjustable power load is a piece of test equipment that often comes handy in the development of a certain electronics projects. For example, when you are building a power supply, it will come a time when you need to “simulate” a load to see how well your design performs as the load varies. Adding power resistors to the output can sometimes do in a pinch, but often you will not have the right resistor value handy with the right power rating for the test. This is where an adjustable electronic load comes handy. In this article, I’ll show how you can build one using common components available to the electronics hobbyist.

Via Electronics Lab.

This entry was posted on Monday, January 21st, 2013 at 5:00 pm and is filed under project logs. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

One Response to “Building an adjustable constant current load”

  1. David Bley says:

    Unless you match your current sink mosfets, it is better to use a seperate section of the LM324 and a seperate current sampling resistor for each sinking mosfet that has their drains connected. This will ensure current sharing. VGS thresholds can vary considerably from device to device.

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